/* SCTP kernel Implementation
 * (C) Copyright IBM Corp. 2001, 2004
 * Copyright (C) 1999-2001 Cisco, Motorola
 *
 * This file is part of the SCTP kernel implementation
 *
 * These are the definitions needed for the command object.
 *
 * This SCTP implementation  is free software;
 * you can redistribute it and/or modify it under the terms of
 * the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 *
 * This SCTP implementation  is distributed in the hope that it
 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
 *                 ************************
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with GNU CC; see the file COPYING.  If not, write to
 * the Free Software Foundation, 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 *
 * Please send any bug reports or fixes you make to one of the
 * following email addresses:
 *
 * La Monte H.P. Yarroll <piggy@acm.org>
 * Karl Knutson <karl@athena.chicago.il.us>
 * Ardelle Fan <ardelle.fan@intel.com>
 * Sridhar Samudrala <sri@us.ibm.com>
 *
 * Any bugs reported given to us we will try to fix... any fixes shared will
 * be incorporated into the next SCTP release.
 */

#ifndef __net_sctp_command_h__
#define __net_sctp_command_h__

#include <net/sctp/constants.h>
#include <net/sctp/structs.h>

typedef enum {
	SCTP_CMD_NOP = 0,	/* Do nothing. */
	SCTP_CMD_NEW_ASOC,	/* Register a new association.  */
	SCTP_CMD_DELETE_TCB,	/* Delete the current association. */
	SCTP_CMD_NEW_STATE,	/* Enter a new state.  */
	SCTP_CMD_REPORT_TSN,	/* Record the arrival of a TSN.  */
	SCTP_CMD_GEN_SACK,	/* Send a Selective ACK (maybe).  */
	SCTP_CMD_PROCESS_SACK,	/* Process an inbound SACK.  */
	SCTP_CMD_GEN_INIT_ACK,	/* Generate an INIT ACK chunk.  */
	SCTP_CMD_PEER_INIT,	/* Process a INIT from the peer.  */
	SCTP_CMD_GEN_COOKIE_ECHO,	/* Generate a COOKIE ECHO chunk. */
	SCTP_CMD_CHUNK_ULP,	/* Send a chunk to the sockets layer.  */
	SCTP_CMD_EVENT_ULP,	/* Send a notification to the sockets layer. */
	SCTP_CMD_REPLY,		/* Send a chunk to our peer.  */
	SCTP_CMD_SEND_PKT,	/* Send a full packet to our peer.  */
	SCTP_CMD_RETRAN,	/* Mark a transport for retransmission.  */
	SCTP_CMD_ECN_CE,	/* Do delayed CE processing.   */
	SCTP_CMD_ECN_ECNE,	/* Do delayed ECNE processing. */
	SCTP_CMD_ECN_CWR,	/* Do delayed CWR processing.  */
	SCTP_CMD_TIMER_START,	/* Start a timer.  */
	SCTP_CMD_TIMER_RESTART,	/* Restart a timer. */
	SCTP_CMD_TIMER_STOP,	/* Stop a timer. */
	SCTP_CMD_INIT_CHOOSE_TRANSPORT,	/* Choose transport for an INIT. */
	SCTP_CMD_INIT_COUNTER_RESET,	/* Reset init counter. */
	SCTP_CMD_INIT_COUNTER_INC,	/* Increment init counter. */
	SCTP_CMD_INIT_RESTART,	/* High level, do init timer work. */
	SCTP_CMD_COOKIEECHO_RESTART,	/* High level, do cookie-echo timer work. */
	SCTP_CMD_INIT_FAILED,	/* High level, do init failure work. */
	SCTP_CMD_REPORT_DUP,	/* Report a duplicate TSN.  */
	SCTP_CMD_STRIKE,	/* Mark a strike against a transport.  */
	SCTP_CMD_TRANSMIT,	/* Transmit the outqueue. */
	SCTP_CMD_HB_TIMERS_START,	/* Start the heartbeat timers. */
	SCTP_CMD_HB_TIMER_UPDATE,	/* Update a heartbeat timers.  */
	SCTP_CMD_HB_TIMERS_STOP,	/* Stop the heartbeat timers.  */
	SCTP_CMD_TRANSPORT_RESET,	/* Reset the status of a transport. */
	SCTP_CMD_TRANSPORT_ON,	/* Mark the transport as active. */
	SCTP_CMD_REPORT_ERROR,	/* Pass this error back out of the sm. */
	SCTP_CMD_REPORT_BAD_TAG,	/* Verification tags didn't match. */
	SCTP_CMD_PROCESS_CTSN,	/* Sideeffect from shutdown. */
	SCTP_CMD_ASSOC_FAILED,	/* Handle association failure. */
	SCTP_CMD_DISCARD_PACKET,	/* Discard the whole packet. */
	SCTP_CMD_GEN_SHUTDOWN,	/* Generate a SHUTDOWN chunk. */
	SCTP_CMD_UPDATE_ASSOC,	/* Update association information. */
	SCTP_CMD_PURGE_OUTQUEUE,	/* Purge all data waiting to be sent. */
	SCTP_CMD_SETUP_T2,	/* Hi-level, setup T2-shutdown parms.  */
	SCTP_CMD_RTO_PENDING,	/* Set transport's rto_pending. */
	SCTP_CMD_PART_DELIVER,	/* Partial data delivery considerations. */
	SCTP_CMD_RENEGE,	/* Renege data on an association. */
	SCTP_CMD_SETUP_T4,	/* ADDIP, setup T4 RTO timer parms. */
	SCTP_CMD_PROCESS_OPERR,	/* Process an ERROR chunk. */
	SCTP_CMD_REPORT_FWDTSN,	/* Report new cumulative TSN Ack. */
	SCTP_CMD_PROCESS_FWDTSN,	/* Skips were reported, so process further. */
	SCTP_CMD_CLEAR_INIT_TAG,	/* Clears association peer's inittag. */
	SCTP_CMD_DEL_NON_PRIMARY,	/* Removes non-primary peer transports. */
	SCTP_CMD_T3_RTX_TIMERS_STOP,	/* Stops T3-rtx pending timers */
	SCTP_CMD_FORCE_PRIM_RETRAN,	/* Forces retrans. over primary path. */
	SCTP_CMD_SET_SK_ERR,	/* Set sk_err */
	SCTP_CMD_ASSOC_CHANGE,	/* generate and send assoc_change event */
	SCTP_CMD_ADAPTATION_IND,	/* generate and send adaptation event */
	SCTP_CMD_ASSOC_SHKEY,	/* generate the association shared keys */
	SCTP_CMD_T1_RETRAN,	/* Mark for retransmission after T1 timeout  */
	SCTP_CMD_UPDATE_INITTAG,	/* Update peer inittag */
	SCTP_CMD_LAST
} sctp_verb_t;

#define SCTP_CMD_MAX		(SCTP_CMD_LAST - 1)
#define SCTP_CMD_NUM_VERBS	(SCTP_CMD_MAX + 1)

/* How many commands can you put in an sctp_cmd_seq_t?
 * This is a rather arbitrary number, ideally derived from a careful
 * analysis of the state functions, but in reality just taken from
 * thin air in the hopes othat we don't trigger a kernel panic.
 */
#define SCTP_MAX_NUM_COMMANDS 14

typedef union {
	__s32 i32;
	__u32 u32;
	__be32 be32;
	__u16 u16;
	__u8 u8;
	int error;
	__be16 err;
	sctp_state_t state;
	sctp_event_timeout_t to;
	unsigned long zero;
	void *ptr;
	struct sctp_chunk *chunk;
	struct sctp_association *asoc;
	struct sctp_transport *transport;
	struct sctp_bind_addr *bp;
	sctp_init_chunk_t *init;
	struct sctp_ulpevent *ulpevent;
	struct sctp_packet *packet;
	sctp_sackhdr_t *sackh;
} sctp_arg_t;

/* We are simulating ML type constructors here.
 *
 * SCTP_ARG_CONSTRUCTOR(NAME, TYPE, ELT) builds a function called
 * SCTP_NAME() which takes an argument of type TYPE and returns an
 * sctp_arg_t.  It does this by inserting the sole argument into the
 * ELT union element of a local sctp_arg_t.
 *
 * E.g., SCTP_ARG_CONSTRUCTOR(I32, __s32, i32) builds SCTP_I32(arg),
 * which takes an __s32 and returns a sctp_arg_t containing the
 * __s32.  So, after foo = SCTP_I32(arg), foo.i32 == arg.
 */
static inline sctp_arg_t SCTP_NULL(void)
{
	sctp_arg_t retval;
	retval.ptr = NULL;
	return retval;
}

static inline sctp_arg_t SCTP_NOFORCE(void)
{
	sctp_arg_t retval = {.zero = 0UL };
	retval.i32 = 0;
	return retval;
}

static inline sctp_arg_t SCTP_FORCE(void)
{
	sctp_arg_t retval = {.zero = 0UL };
	retval.i32 = 1;
	return retval;
}

#define SCTP_ARG_CONSTRUCTOR(name, type, elt) \
static inline sctp_arg_t	\
SCTP_## name (type arg)		\
{ sctp_arg_t retval = {.zero = 0UL}; retval.elt = arg; return retval; }

SCTP_ARG_CONSTRUCTOR(I32, __s32, i32)
    SCTP_ARG_CONSTRUCTOR(U32, __u32, u32)
    SCTP_ARG_CONSTRUCTOR(BE32, __be32, be32)
    SCTP_ARG_CONSTRUCTOR(U16, __u16, u16)
    SCTP_ARG_CONSTRUCTOR(U8, __u8, u8)
    SCTP_ARG_CONSTRUCTOR(ERROR, int, error)
    SCTP_ARG_CONSTRUCTOR(PERR, __be16, err)	/* protocol error */
    SCTP_ARG_CONSTRUCTOR(STATE, sctp_state_t, state)
    SCTP_ARG_CONSTRUCTOR(TO, sctp_event_timeout_t, to)
SCTP_ARG_CONSTRUCTOR(PTR, void *, ptr)
SCTP_ARG_CONSTRUCTOR(CHUNK, struct sctp_chunk *, chunk)
SCTP_ARG_CONSTRUCTOR(ASOC, struct sctp_association *, asoc)
SCTP_ARG_CONSTRUCTOR(TRANSPORT, struct sctp_transport *, transport)
SCTP_ARG_CONSTRUCTOR(BA, struct sctp_bind_addr *, bp)
SCTP_ARG_CONSTRUCTOR(PEER_INIT, sctp_init_chunk_t *, init)
SCTP_ARG_CONSTRUCTOR(ULPEVENT, struct sctp_ulpevent *, ulpevent)
SCTP_ARG_CONSTRUCTOR(PACKET, struct sctp_packet *, packet)
SCTP_ARG_CONSTRUCTOR(SACKH, sctp_sackhdr_t *, sackh)

typedef struct {
	sctp_arg_t obj;
	sctp_verb_t verb;
} sctp_cmd_t;

typedef struct {
	sctp_cmd_t cmds[SCTP_MAX_NUM_COMMANDS];
	__u8 next_free_slot;
	__u8 next_cmd;
} sctp_cmd_seq_t;

/* Initialize a block of memory as a command sequence.
 * Return 0 if the initialization fails.
 */
int sctp_init_cmd_seq(sctp_cmd_seq_t * seq);

/* Add a command to an sctp_cmd_seq_t.
 *
 * Use the SCTP_* constructors defined by SCTP_ARG_CONSTRUCTOR() above
 * to wrap data which goes in the obj argument.
 */
void sctp_add_cmd_sf(sctp_cmd_seq_t * seq, sctp_verb_t verb, sctp_arg_t obj);

/* Return the next command structure in an sctp_cmd_seq.
 * Return NULL at the end of the sequence.
 */
sctp_cmd_t *sctp_next_cmd(sctp_cmd_seq_t * seq);

#endif /* __net_sctp_command_h__ */
